Had cataract op 4 days ago. Go for it!
You will be given the choice of 2 different lenses - not going to try and explain but you will definitely be able to ask questions etc before making your decision, and will have to sign a consent form, so can still refuse to have the op at that point. Don't be put off by the list of things that can go wrong - they have to cover themselves.
You will most definitely not LOSE sight. I have always been very shortsighted, with a massive difference between my eyes, which I didn't know was very unusual until the surgeon told me, The worst eye was operated on and I can now see better through that one than my other. I chose the distance lens - which doesn't make you 'longsighted' incidentally.
Takes time to settle, and you will need new glasses eventually but it is most definitely worth it.
The only downside - saw myself in the bathroom mirror a couple of days after the op and was horrified by this ancient wrinkled 76 year old staring back at me!
Good luck!